GRADE "A" CORK MACHINED TO ACCEPT FUJI'S "HPS" REEL SEATS (TO COMPLETE THE IPSM REEL SEAT SET-UP). THEY PROVIDE A FACTORY FIT TO THE EXTENDED BARREL OF THE SEAT AND A 3/8" DIAMETER FRONT HOLE THAT CAN BE REAMED TO THE EXACT DIAMETER OF THE ROD BEING FITTED.